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Bouncing off rev limiter?

Old Aug 5, 2009 | 09:17 PM
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Default Bouncing off rev limiter?

I have a built 60e from Transformance and Yank 4k stall in my TA. Needless to say I'm blowing the tires off in first but I can't keep it from hitting the rev limiter. I have lowered my shift point to 5600 / 28mph in first gear and it's still hitting the rev limiter at 7200 / 46mph. I have also tried messing with the shift timing but it doesn't seem to be making a difference. Any ideas on what's going on?
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Old Aug 6, 2009 | 10:24 AM
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I had a similar problem with the rev limiter issue, cause of mine was a 3800 stall with 2.73 gears. The difference was too great between the two and I would hit the limiter in 2nd and 3rd. Eventually would have to back out of the throttle to make it shift. Needless to say the transmission was slipping and i eventually blew out 3-4. I lowered my shift point as low as 5500, but it still bounced. Simply put, I had the wrong combination.
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Old Aug 6, 2009 | 12:23 PM
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I don't think I'm getting any abnormal tranny slip other than the converter of course. Should I just keep lowering my shift points and see if it will shift on its own?
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Old Aug 6, 2009 | 01:00 PM
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I would first want to make sure the comand is actually being given you might find the simple tool i describe bellow helpfull in doing this .

How to make a cool tool monitor to know what you trans is being told to do and when.

--------------------------------------------------------------------------------

Parts- all from radio shack cheap
1-Three 12v LEDs They can be different colors(NO LIGHT BULBS WILL NOT WORK)
2-Some sort of bevel to mount them in Or you can mount them in a panel in your car permanent.
3-Three lengths of wire. Perferably different colors to avoid confusion.
4-Blue side wire splicers the type you use pliers to push down the tab to make a splice.

Ok you want to hook the three wires to the following in the harness either at the trans or find them at the PCM
A-Light green wire. This is the 1-2 shift solenoid.
B-Yellow with black stripe. This is the 2-3 shift solenoid
C-Tan wire with black stripe. This is the lockup (TCC)
solenoid.

Do not cut the wires use the slicers and connect your wires one to each and then run them into the car.
Inside the car take each wire and hook up to the negative side of the LEDs choose which ones you want to represent each solenoid.
Tie the POSITIVE side of all the LEDs together and run a wire to a 12v switched source(radio fuse)

Ok now its simple

(1-2)on and (2-3) on is 1st gear
(1-2)off and (2-3) on is second gear
(both off ) is 3rd gear
(1-2)on and (2-3) off is 4th gear
TCC on means your converter should be locked.


This IMO is cool and helpful no more will you wonder if that 2-3 shift that hit the limiter was tuning or trans related and you will know the time from comand to actual shift watching when the lights iluminate and feeling when the shift happens. This could be usefull when setting shift poits since the time is a constant.

No more wondering wether your converter not being locked is a tuning or transmission issue you will see when and if the PCM comands lockup and this can all be done for less than $10 and 30 minutes setting it up.

Hope someone finds this usefull was thinking I have explained this a dozen times to people trying to solve various lockup and shifting issue and may or may not have scanner tools and its proved invaluable to them so why not just post it for anyone who might wanna make a new toy/gadget.
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Old Aug 6, 2009 | 03:11 PM
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Make sure your downshift mph isn't too high.I set shift timing to 0,TM to 0 and ussually raise the pressures on 1-2 ,3-4 WOT on built tranny's.
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Old Aug 6, 2009 | 03:23 PM
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this should be a sticky. thanks i know what i am doing tonight.




Originally Posted by performabuilt
I would first want to make sure the comand is actually being given you might find the simple tool i describe bellow helpfull in doing this .

How to make a cool tool monitor to know what you trans is being told to do and when.

--------------------------------------------------------------------------------

Parts- all from radio shack cheap
1-Three 12v LEDs They can be different colors(NO LIGHT BULBS WILL NOT WORK)
2-Some sort of bevel to mount them in Or you can mount them in a panel in your car permanent.
3-Three lengths of wire. Perferably different colors to avoid confusion.
4-Blue side wire splicers the type you use pliers to push down the tab to make a splice.

Ok you want to hook the three wires to the following in the harness either at the trans or find them at the PCM
A-Light green wire. This is the 1-2 shift solenoid.
B-Yellow with black stripe. This is the 2-3 shift solenoid
C-Tan wire with black stripe. This is the lockup (TCC)
solenoid.

Do not cut the wires use the slicers and connect your wires one to each and then run them into the car.
Inside the car take each wire and hook up to the negative side of the LEDs choose which ones you want to represent each solenoid.
Tie the POSITIVE side of all the LEDs together and run a wire to a 12v switched source(radio fuse)

Ok now its simple

(1-2)on and (2-3) on is 1st gear
(1-2)off and (2-3) on is second gear
(both off ) is 3rd gear
(1-2)on and (2-3) off is 4th gear
TCC on means your converter should be locked.


This IMO is cool and helpful no more will you wonder if that 2-3 shift that hit the limiter was tuning or trans related and you will know the time from comand to actual shift watching when the lights iluminate and feeling when the shift happens. This could be usefull when setting shift poits since the time is a constant.

No more wondering wether your converter not being locked is a tuning or transmission issue you will see when and if the PCM comands lockup and this can all be done for less than $10 and 30 minutes setting it up.

Hope someone finds this usefull was thinking I have explained this a dozen times to people trying to solve various lockup and shifting issue and may or may not have scanner tools and its proved invaluable to them so why not just post it for anyone who might wanna make a new toy/gadget.
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Old Aug 6, 2009 | 04:12 PM
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If you have a scan tool then you can catch RPM
and Trans Current Gear, which is the "start to shift"
point while RPM actually turning back down is the
endpoint. These two can show you PCM intention
and whether the trans is keeping up.
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Old Aug 6, 2009 | 10:05 PM
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Originally Posted by Slowhawk
Make sure your downshift mph isn't too high.I set shift timing to 0,TM to 0 and ussually raise the pressures on 1-2 ,3-4 WOT on built tranny's.
How much are you raising the pressure on the WOT shifts? My fuel pump died yesterday so I have to replace that tomorrow and then I'm going to do some more logging this weekend and try some changes. Thanks for the help guys.
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